1. Field of the Invention
The present invention relates to a radiographic imaging apparatus and a control method for the apparatus.
2. Description of the Related Art
Digital radiographic imaging apparatuses using DR (Digital Radiography) are mainly used for still image capturing. Such a digital radiographic imaging apparatus is smaller in size and lighter in weight than an I.I. TV imaging system having a similar imaging area, and hence is used for moving image capturing. Therefore, the market is demanding a radiation detector that can perform both still image capturing using an electronic cassette (using DR) and moving image capturing that is performed while the cassette is placed on a table or platform.
An electronic cassette using DR requires higher power consumption when performing continuous shooting or moving image capturing than when performing still image capturing. For this reason, when this cassette is placed on a support base such as a table or platform, a cooling mechanism is placed on the support base. There is known a technique of controlling the driving of the cooling mechanism based on the detection of a temperature inside the cassette (Japanese Patent Laid-Open No. 2009-28234).
When an electronic cassette is used while being placed on a support base, the electronic cassette does not come into contact with a patient. For this reason, there is no need to satisfy the exterior temperature requirement for the electronic cassette. However, when the electronic cassette is removed from the support base, the electronic cassette needs to satisfy the exterior temperature requirement.
In general, as a cooling mechanism, a fan is often used because of its low cost and simple arrangement. When, however, cooling is always performed by using the fan, motor sound noise and power consumption are uselessly large, resulting in inefficiency. This gives an object a feeling of discomfort. According to the technique disclosed in Japanese Patent Laid-Open No. 2009-28234 described above, for example, since only a temperature detection result in a cassette is used as a control criterion for cooling, cooling is always performed to satisfy the exterior temperature requirement for the cassette regardless of whether moving image capturing or still image capturing is performed. For this reason, for example, unnecessary cooling is performed even at the time of still image capturing.